Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.15.
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* SCTP kernel implementation
  3 * (C) Copyright Red Hat Inc. 2017
  4 *
  5 * This file is part of the SCTP kernel implementation
  6 *
  7 * These functions implement sctp diag support.
  8 *
  9 * Please send any bug reports or fixes you make to the
 10 * email addresched(es):
 11 *    lksctp developers <linux-sctp@vger.kernel.org>
 12 *
 13 * Written or modified by:
 14 *    Xin Long <lucien.xin@gmail.com>
 15 */
 16
 17#include <linux/module.h>
 18#include <linux/inet_diag.h>
 19#include <linux/sock_diag.h>
 20#include <net/sctp/sctp.h>
 21
 22static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 23			       void *info);
 24
 25/* define some functions to make asoc/ep fill look clean */
 26static void inet_diag_msg_sctpasoc_fill(struct inet_diag_msg *r,
 27					struct sock *sk,
 28					struct sctp_association *asoc)
 29{
 30	union sctp_addr laddr, paddr;
 31	struct dst_entry *dst;
 32	struct timer_list *t3_rtx = &asoc->peer.primary_path->T3_rtx_timer;
 33
 34	laddr = list_entry(asoc->base.bind_addr.address_list.next,
 35			   struct sctp_sockaddr_entry, list)->a;
 36	paddr = asoc->peer.primary_path->ipaddr;
 37	dst = asoc->peer.primary_path->dst;
 38
 39	r->idiag_family = sk->sk_family;
 40	r->id.idiag_sport = htons(asoc->base.bind_addr.port);
 41	r->id.idiag_dport = htons(asoc->peer.port);
 42	r->id.idiag_if = dst ? dst->dev->ifindex : 0;
 43	sock_diag_save_cookie(sk, r->id.idiag_cookie);
 44
 45#if IS_ENABLED(CONFIG_IPV6)
 46	if (sk->sk_family == AF_INET6) {
 47		*(struct in6_addr *)r->id.idiag_src = laddr.v6.sin6_addr;
 48		*(struct in6_addr *)r->id.idiag_dst = paddr.v6.sin6_addr;
 49	} else
 50#endif
 51	{
 52		memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
 53		memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
 54
 55		r->id.idiag_src[0] = laddr.v4.sin_addr.s_addr;
 56		r->id.idiag_dst[0] = paddr.v4.sin_addr.s_addr;
 57	}
 58
 59	r->idiag_state = asoc->state;
 60	if (timer_pending(t3_rtx)) {
 61		r->idiag_timer = SCTP_EVENT_TIMEOUT_T3_RTX;
 62		r->idiag_retrans = asoc->rtx_data_chunks;
 63		r->idiag_expires = jiffies_to_msecs(t3_rtx->expires - jiffies);
 64	} else {
 65		r->idiag_timer = 0;
 66		r->idiag_retrans = 0;
 67		r->idiag_expires = 0;
 68	}
 69}
 70
 71static int inet_diag_msg_sctpladdrs_fill(struct sk_buff *skb,
 72					 struct list_head *address_list)
 73{
 74	struct sctp_sockaddr_entry *laddr;
 75	int addrlen = sizeof(struct sockaddr_storage);
 76	int addrcnt = 0;
 77	struct nlattr *attr;
 78	void *info = NULL;
 79
 80	list_for_each_entry_rcu(laddr, address_list, list)
 81		addrcnt++;
 82
 83	attr = nla_reserve(skb, INET_DIAG_LOCALS, addrlen * addrcnt);
 84	if (!attr)
 85		return -EMSGSIZE;
 86
 87	info = nla_data(attr);
 88	list_for_each_entry_rcu(laddr, address_list, list) {
 89		memcpy(info, &laddr->a, sizeof(laddr->a));
 90		memset(info + sizeof(laddr->a), 0, addrlen - sizeof(laddr->a));
 91		info += addrlen;
 92	}
 93
 94	return 0;
 95}
 96
 97static int inet_diag_msg_sctpaddrs_fill(struct sk_buff *skb,
 98					struct sctp_association *asoc)
 99{
100	int addrlen = sizeof(struct sockaddr_storage);
101	struct sctp_transport *from;
102	struct nlattr *attr;
103	void *info = NULL;
104
105	attr = nla_reserve(skb, INET_DIAG_PEERS,
106			   addrlen * asoc->peer.transport_count);
107	if (!attr)
108		return -EMSGSIZE;
109
110	info = nla_data(attr);
111	list_for_each_entry(from, &asoc->peer.transport_addr_list,
112			    transports) {
113		memcpy(info, &from->ipaddr, sizeof(from->ipaddr));
114		memset(info + sizeof(from->ipaddr), 0,
115		       addrlen - sizeof(from->ipaddr));
116		info += addrlen;
117	}
118
119	return 0;
120}
121
122/* sctp asoc/ep fill*/
123static int inet_sctp_diag_fill(struct sock *sk, struct sctp_association *asoc,
124			       struct sk_buff *skb,
125			       const struct inet_diag_req_v2 *req,
126			       struct user_namespace *user_ns,
127			       int portid, u32 seq, u16 nlmsg_flags,
128			       const struct nlmsghdr *unlh,
129			       bool net_admin)
130{
131	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
132	struct list_head *addr_list;
133	struct inet_diag_msg *r;
134	struct nlmsghdr  *nlh;
135	int ext = req->idiag_ext;
136	struct sctp_infox infox;
137	void *info = NULL;
138
139	nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
140			nlmsg_flags);
141	if (!nlh)
142		return -EMSGSIZE;
143
144	r = nlmsg_data(nlh);
145	BUG_ON(!sk_fullsock(sk));
146
147	if (asoc) {
148		inet_diag_msg_sctpasoc_fill(r, sk, asoc);
149	} else {
150		inet_diag_msg_common_fill(r, sk);
151		r->idiag_state = sk->sk_state;
152		r->idiag_timer = 0;
153		r->idiag_retrans = 0;
154	}
155
156	if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin))
157		goto errout;
158
159	if (ext & (1 << (INET_DIAG_SKMEMINFO - 1))) {
160		u32 mem[SK_MEMINFO_VARS];
161		int amt;
162
163		if (asoc && asoc->ep->sndbuf_policy)
164			amt = asoc->sndbuf_used;
165		else
166			amt = sk_wmem_alloc_get(sk);
167		mem[SK_MEMINFO_WMEM_ALLOC] = amt;
168		if (asoc && asoc->ep->rcvbuf_policy)
169			amt = atomic_read(&asoc->rmem_alloc);
170		else
171			amt = sk_rmem_alloc_get(sk);
172		mem[SK_MEMINFO_RMEM_ALLOC] = amt;
173		mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
174		mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
175		mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
176		mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
177		mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
178		mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
179		mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
180
181		if (nla_put(skb, INET_DIAG_SKMEMINFO, sizeof(mem), &mem) < 0)
182			goto errout;
183	}
184
185	if (ext & (1 << (INET_DIAG_INFO - 1))) {
186		struct nlattr *attr;
187
188		attr = nla_reserve_64bit(skb, INET_DIAG_INFO,
189					 sizeof(struct sctp_info),
190					 INET_DIAG_PAD);
191		if (!attr)
192			goto errout;
193
194		info = nla_data(attr);
195	}
196	infox.sctpinfo = (struct sctp_info *)info;
197	infox.asoc = asoc;
198	sctp_diag_get_info(sk, r, &infox);
199
200	addr_list = asoc ? &asoc->base.bind_addr.address_list
201			 : &ep->base.bind_addr.address_list;
202	if (inet_diag_msg_sctpladdrs_fill(skb, addr_list))
203		goto errout;
204
205	if (asoc && (ext & (1 << (INET_DIAG_CONG - 1))))
206		if (nla_put_string(skb, INET_DIAG_CONG, "reno") < 0)
207			goto errout;
208
209	if (asoc && inet_diag_msg_sctpaddrs_fill(skb, asoc))
210		goto errout;
211
212	nlmsg_end(skb, nlh);
213	return 0;
214
215errout:
216	nlmsg_cancel(skb, nlh);
217	return -EMSGSIZE;
218}
219
220/* callback and param */
221struct sctp_comm_param {
222	struct sk_buff *skb;
223	struct netlink_callback *cb;
224	const struct inet_diag_req_v2 *r;
225	const struct nlmsghdr *nlh;
226	bool net_admin;
227};
228
229static size_t inet_assoc_attr_size(struct sctp_association *asoc)
230{
231	int addrlen = sizeof(struct sockaddr_storage);
232	int addrcnt = 0;
233	struct sctp_sockaddr_entry *laddr;
234
235	list_for_each_entry_rcu(laddr, &asoc->base.bind_addr.address_list,
236				list)
237		addrcnt++;
238
239	return	  nla_total_size(sizeof(struct sctp_info))
240		+ nla_total_size(1) /* INET_DIAG_SHUTDOWN */
241		+ nla_total_size(1) /* INET_DIAG_TOS */
242		+ nla_total_size(1) /* INET_DIAG_TCLASS */
243		+ nla_total_size(4) /* INET_DIAG_MARK */
244		+ nla_total_size(4) /* INET_DIAG_CLASS_ID */
245		+ nla_total_size(addrlen * asoc->peer.transport_count)
246		+ nla_total_size(addrlen * addrcnt)
247		+ nla_total_size(sizeof(struct inet_diag_meminfo))
248		+ nla_total_size(sizeof(struct inet_diag_msg))
249		+ 64;
250}
251
252static int sctp_tsp_dump_one(struct sctp_transport *tsp, void *p)
253{
254	struct sctp_association *assoc = tsp->asoc;
255	struct sock *sk = tsp->asoc->base.sk;
256	struct sctp_comm_param *commp = p;
257	struct sk_buff *in_skb = commp->skb;
258	const struct inet_diag_req_v2 *req = commp->r;
259	const struct nlmsghdr *nlh = commp->nlh;
260	struct net *net = sock_net(in_skb->sk);
261	struct sk_buff *rep;
262	int err;
263
264	err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
265	if (err)
266		goto out;
267
268	err = -ENOMEM;
269	rep = nlmsg_new(inet_assoc_attr_size(assoc), GFP_KERNEL);
270	if (!rep)
271		goto out;
272
273	lock_sock(sk);
274	if (sk != assoc->base.sk) {
275		release_sock(sk);
276		sk = assoc->base.sk;
277		lock_sock(sk);
278	}
279	err = inet_sctp_diag_fill(sk, assoc, rep, req,
280				  sk_user_ns(NETLINK_CB(in_skb).sk),
281				  NETLINK_CB(in_skb).portid,
282				  nlh->nlmsg_seq, 0, nlh,
283				  commp->net_admin);
284	release_sock(sk);
285	if (err < 0) {
286		WARN_ON(err == -EMSGSIZE);
287		kfree_skb(rep);
288		goto out;
289	}
290
291	err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
292			      MSG_DONTWAIT);
293	if (err > 0)
294		err = 0;
295out:
296	return err;
297}
298
299static int sctp_sock_dump(struct sctp_transport *tsp, void *p)
300{
301	struct sctp_endpoint *ep = tsp->asoc->ep;
302	struct sctp_comm_param *commp = p;
303	struct sock *sk = ep->base.sk;
304	struct sk_buff *skb = commp->skb;
305	struct netlink_callback *cb = commp->cb;
306	const struct inet_diag_req_v2 *r = commp->r;
307	struct sctp_association *assoc;
308	int err = 0;
309
310	lock_sock(sk);
311	list_for_each_entry(assoc, &ep->asocs, asocs) {
312		if (cb->args[4] < cb->args[1])
313			goto next;
314
315		if (r->id.idiag_sport != htons(assoc->base.bind_addr.port) &&
316		    r->id.idiag_sport)
317			goto next;
318		if (r->id.idiag_dport != htons(assoc->peer.port) &&
319		    r->id.idiag_dport)
320			goto next;
321
322		if (!cb->args[3] &&
323		    inet_sctp_diag_fill(sk, NULL, skb, r,
324					sk_user_ns(NETLINK_CB(cb->skb).sk),
325					NETLINK_CB(cb->skb).portid,
326					cb->nlh->nlmsg_seq,
327					NLM_F_MULTI, cb->nlh,
328					commp->net_admin) < 0) {
329			err = 1;
330			goto release;
331		}
332		cb->args[3] = 1;
333
334		if (inet_sctp_diag_fill(sk, assoc, skb, r,
335					sk_user_ns(NETLINK_CB(cb->skb).sk),
336					NETLINK_CB(cb->skb).portid,
337					cb->nlh->nlmsg_seq, 0, cb->nlh,
338					commp->net_admin) < 0) {
339			err = 1;
340			goto release;
341		}
342next:
343		cb->args[4]++;
344	}
345	cb->args[1] = 0;
346	cb->args[3] = 0;
347	cb->args[4] = 0;
348release:
349	release_sock(sk);
350	return err;
351}
352
353static int sctp_sock_filter(struct sctp_transport *tsp, void *p)
354{
355	struct sctp_endpoint *ep = tsp->asoc->ep;
356	struct sctp_comm_param *commp = p;
357	struct sock *sk = ep->base.sk;
358	const struct inet_diag_req_v2 *r = commp->r;
359	struct sctp_association *assoc =
360		list_entry(ep->asocs.next, struct sctp_association, asocs);
361
362	/* find the ep only once through the transports by this condition */
363	if (tsp->asoc != assoc)
364		return 0;
365
366	if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family)
367		return 0;
368
369	return 1;
370}
371
372static int sctp_ep_dump(struct sctp_endpoint *ep, void *p)
373{
374	struct sctp_comm_param *commp = p;
375	struct sock *sk = ep->base.sk;
376	struct sk_buff *skb = commp->skb;
377	struct netlink_callback *cb = commp->cb;
378	const struct inet_diag_req_v2 *r = commp->r;
379	struct net *net = sock_net(skb->sk);
380	struct inet_sock *inet = inet_sk(sk);
381	int err = 0;
382
383	if (!net_eq(sock_net(sk), net))
384		goto out;
385
386	if (cb->args[4] < cb->args[1])
387		goto next;
388
389	if (!(r->idiag_states & TCPF_LISTEN) && !list_empty(&ep->asocs))
390		goto next;
391
392	if (r->sdiag_family != AF_UNSPEC &&
393	    sk->sk_family != r->sdiag_family)
394		goto next;
395
396	if (r->id.idiag_sport != inet->inet_sport &&
397	    r->id.idiag_sport)
398		goto next;
399
400	if (r->id.idiag_dport != inet->inet_dport &&
401	    r->id.idiag_dport)
402		goto next;
403
404	if (inet_sctp_diag_fill(sk, NULL, skb, r,
405				sk_user_ns(NETLINK_CB(cb->skb).sk),
406				NETLINK_CB(cb->skb).portid,
407				cb->nlh->nlmsg_seq, NLM_F_MULTI,
408				cb->nlh, commp->net_admin) < 0) {
409		err = 2;
410		goto out;
411	}
412next:
413	cb->args[4]++;
414out:
415	return err;
416}
417
418/* define the functions for sctp_diag_handler*/
419static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
420			       void *info)
421{
422	struct sctp_infox *infox = (struct sctp_infox *)info;
423
424	if (infox->asoc) {
425		r->idiag_rqueue = atomic_read(&infox->asoc->rmem_alloc);
426		r->idiag_wqueue = infox->asoc->sndbuf_used;
427	} else {
428		r->idiag_rqueue = sk->sk_ack_backlog;
429		r->idiag_wqueue = sk->sk_max_ack_backlog;
430	}
431	if (infox->sctpinfo)
432		sctp_get_sctp_info(sk, infox->asoc, infox->sctpinfo);
433}
434
435static int sctp_diag_dump_one(struct sk_buff *in_skb,
436			      const struct nlmsghdr *nlh,
437			      const struct inet_diag_req_v2 *req)
438{
439	struct net *net = sock_net(in_skb->sk);
440	union sctp_addr laddr, paddr;
441	struct sctp_comm_param commp = {
442		.skb = in_skb,
443		.r = req,
444		.nlh = nlh,
445		.net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN),
446	};
447
448	if (req->sdiag_family == AF_INET) {
449		laddr.v4.sin_port = req->id.idiag_sport;
450		laddr.v4.sin_addr.s_addr = req->id.idiag_src[0];
451		laddr.v4.sin_family = AF_INET;
452
453		paddr.v4.sin_port = req->id.idiag_dport;
454		paddr.v4.sin_addr.s_addr = req->id.idiag_dst[0];
455		paddr.v4.sin_family = AF_INET;
456	} else {
457		laddr.v6.sin6_port = req->id.idiag_sport;
458		memcpy(&laddr.v6.sin6_addr, req->id.idiag_src,
459		       sizeof(laddr.v6.sin6_addr));
460		laddr.v6.sin6_family = AF_INET6;
461
462		paddr.v6.sin6_port = req->id.idiag_dport;
463		memcpy(&paddr.v6.sin6_addr, req->id.idiag_dst,
464		       sizeof(paddr.v6.sin6_addr));
465		paddr.v6.sin6_family = AF_INET6;
466	}
467
468	return sctp_transport_lookup_process(sctp_tsp_dump_one,
469					     net, &laddr, &paddr, &commp);
470}
471
472static void sctp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
473			   const struct inet_diag_req_v2 *r, struct nlattr *bc)
474{
475	u32 idiag_states = r->idiag_states;
476	struct net *net = sock_net(skb->sk);
477	struct sctp_comm_param commp = {
478		.skb = skb,
479		.cb = cb,
480		.r = r,
481		.net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN),
482	};
483	int pos = cb->args[2];
484
485	/* eps hashtable dumps
486	 * args:
487	 * 0 : if it will traversal listen sock
488	 * 1 : to record the sock pos of this time's traversal
489	 * 4 : to work as a temporary variable to traversal list
490	 */
491	if (cb->args[0] == 0) {
492		if (!(idiag_states & TCPF_LISTEN))
493			goto skip;
494		if (sctp_for_each_endpoint(sctp_ep_dump, &commp))
495			goto done;
496skip:
497		cb->args[0] = 1;
498		cb->args[1] = 0;
499		cb->args[4] = 0;
500	}
501
502	/* asocs by transport hashtable dump
503	 * args:
504	 * 1 : to record the assoc pos of this time's traversal
505	 * 2 : to record the transport pos of this time's traversal
506	 * 3 : to mark if we have dumped the ep info of the current asoc
507	 * 4 : to work as a temporary variable to traversal list
508	 * 5 : to save the sk we get from travelsing the tsp list.
509	 */
510	if (!(idiag_states & ~(TCPF_LISTEN | TCPF_CLOSE)))
511		goto done;
512
513	sctp_for_each_transport(sctp_sock_filter, sctp_sock_dump,
514				net, &pos, &commp);
515	cb->args[2] = pos;
516
517done:
518	cb->args[1] = cb->args[4];
519	cb->args[4] = 0;
520}
521
522static const struct inet_diag_handler sctp_diag_handler = {
523	.dump		 = sctp_diag_dump,
524	.dump_one	 = sctp_diag_dump_one,
525	.idiag_get_info  = sctp_diag_get_info,
526	.idiag_type	 = IPPROTO_SCTP,
527	.idiag_info_size = sizeof(struct sctp_info),
528};
529
530static int __init sctp_diag_init(void)
531{
532	return inet_diag_register(&sctp_diag_handler);
533}
534
535static void __exit sctp_diag_exit(void)
536{
537	inet_diag_unregister(&sctp_diag_handler);
538}
539
540module_init(sctp_diag_init);
541module_exit(sctp_diag_exit);
542MODULE_LICENSE("GPL");
543MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-132);